class CodeVerfiy {
  constructor(options) {
    this.options = {
      id: "", // 容器Id
      canvasId: "verifyCanvas", // canvas的id
      width: "100", // 默认canvas宽度
      height: "35", // 默认canvas高度
      type: "blend", // 图形验证码默认类型blend:数字字母混合类型、number:纯数字、letter:纯字母
      code: "",
      defaultCode: "",
    };

    if (Object.prototype.toString.call(options) == "[object Object]") {
      // 判断传入参数类型
      for (var i in options) {
        // 根据传入的参数，修改默认参数值
        this.options[i] = options[i];
      }
    } else {
      this.options.id = options;
    }

    this.options.numArr = "0,1,2,3,4,5,6,7,8,9".split(",");
    this.options.letterArr = this.getAllLetter();

    this.init();
    this.refresh(this.options.defaultCode);
  }
  init() {
    var con = document.getElementById(this.options.id);
    var canvas = document.createElement("canvas");
    this.options.width =
      Number(this.options.width) > 0 ? this.options.width : con.offsetWidth;
    this.options.height =
      Number(this.options.height) > 0 ? this.options.height : con.offsetHeight;
    canvas.id = this.options.canvasId;
    canvas.width = this.options.width;
    canvas.height = this.options.height;
    canvas.style.cursor = "pointer";
    canvas.innerHTML = "您的浏览器版本不支持canvas";
    con.appendChild(canvas);
    // var parent = this;
    // canvas.onclick = function() {
    //   parent.refresh();
    // };
  }

  /** 生成验证码* */
  refresh(defaultCode) {
    this.options.code = "";
    var canvas = document.getElementById(this.options.canvasId);
    if (canvas.getContext) {
      var ctx = canvas.getContext("2d");
    } else {
      return;
    }

    ctx.textBaseline = "middle";

    ctx.fillStyle = this.randomColor(180, 240);
    ctx.fillRect(0, 0, this.options.width, this.options.height);

    //   if(this.options.type == "blend") { // 判断验证码类型
    //       var txtArr = this.options.numArr.concat(this.options.letterArr);
    //   } else if(this.options.type == "number") {
    //       var txtArr = this.options.numArr;
    //   } else {
    //       var txtArr = this.options.letterArr;
    //   }
    let txtArr = defaultCode.split("");

    for (var i = 1; i <= 4; i++) {
      var txt = txtArr[i - 1];
      this.options.code += txt;
      ctx.font =
        this.randomNum(this.options.height / 1.3, this.options.height) +
        "px SimHei"; // 随机生成字体大小
      ctx.fillStyle = this.randomColor(50, 160); // 随机生成字体颜色
      ctx.shadowOffsetX = this.randomNum(-3, 3);
      ctx.shadowOffsetY = this.randomNum(-3, 3);
      ctx.shadowBlur = this.randomNum(-3, 3);
      ctx.shadowColor = "rgba(0, 0, 0, 0.5)";
      var x = (this.options.width / 5) * i;
      var y = this.options.height / 2;
      var deg = this.randomNum(-30, 30);
      /** 设置旋转角度和坐标原点* */
      ctx.translate(x, y);
      ctx.rotate((deg * Math.PI) / 180);
      ctx.fillText(txt, 0, 0);
      /** 恢复旋转角度和坐标原点* */
      ctx.rotate((-deg * Math.PI) / 180);
      ctx.translate(-x, -y);
    }
    /** 绘制干扰点* */
    for (var i = 0; i < this.options.width / 4; i++) {
      ctx.fillStyle = this.randomColor(0, 255);
      ctx.beginPath();
      ctx.arc(
        this.randomNum(0, this.options.width),
        this.randomNum(0, this.options.height),
        1,
        0,
        2 * Math.PI
      );
      ctx.fill();
    }
  }

  /** 验证验证码* */
  validate(code) {
    var code = code.toLowerCase();
    var v_code = this.options.code.toLowerCase();
    if (code === v_code) {
      return true;
    } else {
      return false;
    }
  }
  /** 生成字母数组* */
  getAllLetter() {
    var letterStr =
      "a,b,c,d,e,f,g,h,i,j,k,m,n,o,p,q,r,s,t,u,v,w,x,y,z,A,B,C,D,E,F,G,H,I,J,K,L,M,N,O,P,Q,R,S,T,U,V,W,X,Y,Z";
    return letterStr.split(",");
  }
  /** 生成一个随机色* */
  randomColor(min, max) {
    var r = this.randomNum(min, max);
    var g = this.randomNum(min, max);
    var b = this.randomNum(min, max);
    return "rgb(" + r + "," + g + "," + b + ")";
  }
  /** 生成一个随机数* */
  randomNum(min, max) {
    return Math.floor(Math.random() * (max - min) + min);
  }
}
export default CodeVerfiy;
